The efficiency of the photon capture therapy with gold containing compounds based on hyaluronic acid (experimental study)

The efficiency of the photon capture therapy with synthesized gold-containing nanocomposite for experimental sarcoma M-1 was estimated. To simulate photon capture irradiation the animals were exposed to single X-ray dose of 28 Gy delivered to the tumor following administration of a single dose of gold-containing compound based on hyaluronic acid and melanin. The composite was injected intratumorally in the amount of 4 mg of gold per animal 15 minutes before irradiation. Dynamic curves of tumor growth for 27 days after X-ray exposure of rats with the injected gold composite were similar to tumor growth curves after single local X-ray exposure to 32 Gy. The absorbed dose reduction due to photon-capturing events was 4 Gy (about 14%). Efficiency of experimental photon capture therapy was estimated by comparison of tumor growth inhibition indexes. The experimental photon-capture therapy was by 26% more efficient than local acute X-rays irradiation. No significant difference in skin reactions yield was observed. The obtained results showed the gold-containing nanocomposite based on hyaluronic acid and melanin to be promising agent for photon-capture therapy. The observed difference between therapeutic efficiency estimates due to the use of different criteria, such as relative tumor volume, tumor growth inhibition index, tumor growth factor, irradiation efficiency ratio, skin reactions yield, highlights the need to develop a multifaceted approach for creating the medical technology.